Hey, I just bought a 91 CBR1000F and have been riding it for a couple of days when the battery went dead. I charged it up, and it went dead again. We started it up and took the positive battery cable off and it cut off. What could be causing this, besides the alternator, since its over $700. Any help would be appreciated.

 

You have to ride it around a bit, the alternator doesnt kick in until...I cant remember the exact RPM, but it's higher than idle, so go ride it and see if that helps